This invention is directed to magnetic bubble domain devices and in particular to a gating circuit therefor. More specifically this invention relates to a new replicate/swap gate for bubble memories.
Magnetic bubble gating circuits and organizations, such as storage loops formed of propagate elements in which bubble domains circulate in response to a rotating in-plane magnetic field to form a bubble memory device, are old and well known. See, for example, the U.S. patents to Chen U.S. Pat. No. 4,094,005, Gergis No. 4,079,359, Chang No. 4,122,537 and to Bullock No. 4,086,572.
The above-mentioned Schwartz et al. application disclosed a folded loop configuration as a storage loop in which a number of propagate elements can be selected so as to time the propagation of the bubbles not only in the loop itself but also to time other functional elements in the bubble memory organization. While a number of additional advantages accrue by the use of a folded loop configuration, one advantage set forth was the fact that gating circuits and other functional elements can be located on one end or side of the loop for more efficient exchange of information between the components. Another advantage was the use of a single conductor to perform a number of gating functions.
This invention is directed to a specific embodiment of a gating circuit responsive to different phases of an in-plane rotating magnetic field and with a plurality of gates oriented to be independently operable by a single conductor which is subjected to current pulses of different amplitudes during selected phases of the rotating field and useable in combination with a loop storage arrangement.
Accordingly, it is an object of this invention to provide a gating circuit in the form of a replicate/swap gate operable by a single conductor at selected phases of an in-plane rotating magnetic field and at selected current amplitudes for transferring information to and from a bubble memory storage loop.